Experimental Investigation on Piezoresistive Properties and Acoustic Emission Characteristics of Carbon Fiber-Based Gangue Concrete

Concrete with coal gangue as aggregate has a self-sensing ability with addition of carbon fiber (CF), which has an outstanding effect in terms of dealing with the large amount of coal gangue discharge and monitoring the concrete structure. However, studies on the development of CF-based gangue concrete (CF-GC) with self-sensing capabilities are limited. Therefore, the uniaxial compression tests of CF-GC were carried out and changes in the electrical resistivity (ER) and acoustic emission (AE) characteristics were monitored throughout testing. The test results suggested that the addition of CF can significantly improve the electrical conductivity properties of gangue concrete. Value of gage factor for CF-GC and gangue concrete is 2.3 and 16.6, which the value of gage factor for the CF-GC increased by 14.3 compared with the GC. The research showed a good correlation between the ER and AE of CF-GC, and an increase in curing time led to a decrease in in the electrical conductivity of CF-GC. This study shows that it is of great significance to be able to predict deformations in gangue concrete structures by monitoring changes in ER and AE.